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Objective To determine the diagnostic accuracy and pitfalls of endoscopic ultrasound ( EUS)-guided fine needle aspiration ( FNA) cytology of pancreatic neuroendocrine tumour (Pan NET). Methods A search of our laboratory information system was performed from July 1992 to June 2010 to identify all FNA cytology and corresponding surgical specimens in which the diagnosis of Pan NET was rendered or considered. Results One hundred and thirty-two cases diagnosed by EUS-guided FNA were collected. Histological correlation was available for 77 (58%) of FNAs; 55 patients may have been treated elsewhere or had no surgery because of advanced disease or co-morbidity. Among 56 cases diagnosed as Pan NET on FNA, 54 (96%) were confirmed histologically; the remaining two were poorly differentiated adenocarcinoma with focal neuroendocrine features in one case and no tumour was found in the other. Follow-up histology of nine patients diagnosed as suspicious for Pan NET on FNA showed four Pan NETs, two pancreatic ductal adenocarcinomas ( PDA), one solid pseudopapillary tumour ( SPT) and two cases of chronic pancreatitis. Nine cases rendered by FNA as atypical ( n = 3), no atypical cells identified ( n = 4) or unsatisfactory ( n = 2) were Pan NETs on histology. Lastly, three cases of oncocytic variant of Pan NET were misdiagnosed on FNA as either adenocarcinoma ( n = 2) or as suspicious for carcinoma ( n = 1). Conclusions Overall, 54 of the 70 histologically confirmed Pan NET cases (77%) were correctly diagnosed by preoperative FNA as Pan NET. FNA cases designated as no atypical cells identified and unsatisfactory (7/132, 5%) were attributable to sampling error. Diagnostic pitfalls in our study mainly included PDA, SPT and chronic pancreatitis. [ABSTRACT FROM AUTHOR]

The article discusses a study conducted for understanding slurry flow in hydrates. Topics discussed include deepwater flow leading to flow accidents in pipelines used in oil/gas storage and transportation, use of gas consumption data for estimation of hydrate volume fraction, investigation of feasible conditions for the flow in metastable stage and ensuring safe slurry flow when the actual flow exceeds the minimum flow.

The unusual temperature-induced switching behavior in a ferroelectric single crystal with dislocation arrays is investigated by using phase field simulations. The results show that the influence of temperature on the hysteresis loop of a ferroelectric is dependent on the dislocation arrays. In the presence of dislocation arrays, the dependence of the coercive field on the temperature is different from that of a dislocation-free ferroelectric. The coercive field increases when the temperature increases from room temperature to a critical temperature, which is attributed to the pinning of domains by the dislocation arrays. Above the critical temperature, both the coercive field and the remnant polarization decrease with temperature. It is found that double hysteresis loops can be induced by dislocation arrays when the temperature is higher than the Curie temperature. This work exhibits the complex role of temperature and dislocations in the polarization switching of ferroelectric single crystal. [ABSTRACT FROM AUTHOR]

Planar mirror has been used successfully in catadioptric stereo systems to capture stereo images with a single camera. These planar catadioptric stereo (PCS) systems not only provide radiometric advantages over traditional two-camera stereo, but also reduce the complexity and cost of acquiring stereoscopic video. Although many papers have been published on the design of the PCS system, few studies have been conducted for the analysis of its epipolar geometry, that is, the fundamental matrix. In this study, the authors investigated features of two types of PCS system and verified that they both can be approximated by affine epipolar geometry. This affine property is either because of constraints on the structure of the PCS system or because of the narrow field of view (FOV) of the mirror. This affine model reduces the number of parameters in the fundamental matrix from seven in the conventional stereo system to only four in the PCS system. Experimental results based on various criteria verify that by using the affine model with fewer parameters, estimation of the fundamental matrix for a PCS system can be more robust, precise and much easier to implement. These significant advantages confirm the usefulness of an affine fundamental matrix model for the PCS systems. [ABSTRACT FROM AUTHOR]

For stereo vision applications, projective geometry has proved to be a useful tool for solving the rectification problem without camera calibration. However, the criterion of minimisation for projective rectification must be chosen properly in order to avoid unduly geometric distortion. In this paper, an improved algorithm to minimise the distortion by combining a newly developed projective transform with a properly chosen shearing transform is proposed. The emphasis on low geometric distortion makes this method not only appropriate for 3-D reconstruction but also for stereoscopic viewing applications. On the basis of relative modification, this new method contains fewer parameters (6 degrees of freedom) for minimisation, which reduces the processing time, and improves the rectification result. Several different types of image pairs were tested to demonstrate the applicability and reliability of the proposed algorithm visually and quantitatively. Comparisons with other methods are also provided to verify the improvement of this new scheme. [ABSTRACT FROM AUTHOR]

The extent to which racial minority groups face discrimination in the labor market is the subject of considerable debate. Using William J. Wilson's thesis of the declining significance of race as our theoretical context, we provide further empirical evidence about labor market discrimination by investigating wages among African American, American Indian, Chinese American, Hispanic white, Japanese American, and non-Hispanic white men. We find, during the period before the civil rights movement, that a substantively significant wage disadvantage is evident for these minority groups with controls for observed labor force characteristics. In recent data, these net disadvantages are reduced substantially for each of these groups except Hispanics. With the exception of Hispanics, the results support Wilson's thesis. [ABSTRACT FROM AUTHOR]

The purpose of this study is to explore the alleviation of hair loss syndrome (HLS) by adding mineral supplements to the diet of captive Formosan sambar deer. The experiment was performed in two deer farms, A (without HLS) and B (with HLS). The feeding situation was investigated the crude protein and mineral content intake. Deers were provided with commercial concentrate (control group). The treatment group was additionally given mineral supplements. The results showed that the amount of crude protein and minerals are given in farm A is higher than in farm B. Although there were some significant differences in serum mineral concentrations between the control and the treatment group, both were within the normal range. At the time of sampling, the deer hairs were uniform and glossy. In the hair of the control group, the Ca, P, Na, and Cu content of the hair of farm A was significantly higher than that of farm B (P < 0.05) ; but the treatment group only the Na content of farm A was significantly higher than that of farm B (P < 0.05). The results show that the concentration of minerals in the serum tends to be constant, but the hair mineral content can reflect the supply of minerals for long-term feeding. Nutritional deficiencies may cause hair loss, and additional mineral supplementation should reduce its incidence. [ABSTRACT FROM AUTHOR]

This experiment was aimed to investigate the physiological performance of Nubian, Boer, Renting and Taiwan black goats in the hot season. Three males and females of 4-month-old and 2-year-old goats were randomly selected for each breed. The results showed that the rectal temperature, respiration and heartbeat rate of each breed were significantly higher at 4-month-old goats than that of 2-year-old goats. RBC, Hgb and Hct of Taiwan black goat were significantly higher than the other breeds. The higher values indicate higher oxygen demand to resist the hot environment. CPK was an enzyme produced by heat stress or intensive exercise. Serum TP usually reduced associate with the decrease of feed intake due to heat stress. Serum CPK and TP of Boer and Taiwan black goats were significantly higher than the other breeds. The result showed the significant differences were in blood trait among different breeds of goats. [ABSTRACT FROM AUTHOR]

A metal-oxide-semiconductor structure with NiSi2 nanocrystals embedded in the SiO2 layer has been fabricated. A pronounced capacitance-voltage hysteresis was observed with a memory window of 1 V under the 2 V programming voltage. The processing of the structure is compatible with the current manufacturing technology of semiconductor industry. [ABSTRACT FROM AUTHOR]

Energy conversion between the fields and the particles occurs through various physical processes within space environments. Magnetic reconnection stands out as one such process capable of rapidly and massively releasing energy. The high‐speed outflow jets produced by reconnection can induce turbulence characterized by intermittent structures. In this study, we investigate the impact of guide field on the energy conversion associated with the magnetic topologies within these structures during reconnection. Utilizing both particle‐in‐cell simulations and observations from the Magnetospheric Multiscale mission, our findings suggest that a larger guide field present during reconnection leads to increased energy conversion as well as the generation of O‐type topology structures within the turbulent outflow. Our results provide significant evidence on the relationships between energy conversion and magnetic topologies within turbulent outflow of reconnection and the guide field conditions. Plain Language Summary: In space environments, various physical processes involve the conversion of energy between magnetic fields and particles. One such process is magnetic reconnection, which can rapidly release a large amount of energy. During magnetic reconnection, high‐speed outflow jets are generated, leading to the formation of turbulent structures. In our study, we investigate how the presence of a guide field affects the energy conversion process and the resulting magnetic topologies within these turbulent structures during reconnection events. Using both particle‐in‐cell simulations and observations from the Magnetospheric Multiscale mission, we explore the impact of guide fields on energy conversion and magnetic topologies. Our findings indicate that a larger guide field present during reconnection leads to increased energy conversion and the generation of specific magnetic topology structures known as O‐type topologies within the turbulent outflow. These results provide significant insights into the complex relationships between energy conversion processes, magnetic topologies, and guide field conditions during magnetic reconnection events in space. Understanding these relationships is crucial for advancing our knowledge of fundamental physical processes occurring in space environments. Key Points: Magnetic topology in the turbulent reconnection outflow is investigated through both Magnetospheric Multiscale (MMS) observations and particle‐in‐cell (PIC) simulationsA larger guide field can promote the generation of O‐type topology in the turbulent outflow of the reconnectionHigher energy conversion is contributed by those O‐type topologies in the presence of a larger guide field [ABSTRACT FROM AUTHOR]

While Mars lacks a global intrinsic magnetic field, it does exhibit crustal magnetic anomalies (mostly in its Southern Hemisphere). These crustal magnetic anomalies directly interact with solar wind, which forms a mini‐magnetosphere and a region denoted the mini‐magnetopause. Using magnetic field and plasma measurements from the Mars Atmosphere and Volatile Evolution, we report a novel case of magnetic reconnection at the Martian mini‐magnetopause. In this process, protons and oxygen ions from the Martian atmosphere were accelerated during reconnection and likely escaped along the outflow direction. Magnetic reconnection may occur between the interplanetary magnetic field and crustal magnetic fields at the Martian mini‐magnetopause, which contributes to planetary ion escape, solar wind entering the mini‐magnetosphere and the evolution of magnetic topology in the dayside Martian mini‐magnetosphere. Plain Language Summary: While Mars lacks a global intrinsic magnetic field, it does exhibit crustal magnetic anomalies. The solar wind from the sun accompanied by interplanetary magnetic field (IMF) directly interacts with this crustal magnetic field, similar to what occurs on Earth, albeit at a smaller scale. The boundary between the crustal field on Mars and the IMF is called the mini‐magnetopause. Magnetic reconnection is a fundamental process in astrophysical and space plasmas that can change the topology of magnetic field and effectively convert magnetic energy into thermal and kinetic energy. Using magnetic field and plasma measurements from the Mars Atmosphere and Volatile Evolution missions, we report direction observations of magnetic reconnection at the Martian mini‐magnetopause. Through magnetic reconnection at the mini‐magnetopause, the IMF reconnects with the magnetic field from the crustal field, forming new magnetic field lines that channel solar wind to enter the Martian atmosphere and planetary plasmas to escape. Key Points: Magnetic reconnection at the Martian mini‐magnetopause is reported for the first timeProton and oxygen ions from the mini‐magnetosphere are accelerated during magnetic reconnectionMagnetic reconnection at the mini‐magnetopause could cause solar wind to enter the mini‐magnetosphere [ABSTRACT FROM AUTHOR]